1. Field of the Invention
The present invention relates to disc drive apparatuses which are used for erasing and filling with data on a disc shaped medium (a disc type recording medium) such as a compact disc (CD) and the like, and more particularly to a disc drive apparatus which can read and/or write two kinds of large and small disc shaped media having different diameters.
2. Description of the Related Art
In recent years, disc shaped media such as CD, DVD and the like have come into wide use as a recording medium for a voice and a screen image. Most of the CD and the DVD are unified in a diameter of 12 cm (a large-diameter disc), however, there are disc shaped media having a diameter of 8 cm which are called as a single CD (a small-diameter disc). The two kinds of large and small discs can be generally driven by one apparatus, however, apart from an apparatus structured such that the disc is set manually on a turn table, it is required to accurately position the two kinds of large and small disc shaped media in the disc drive apparatus using a transfer system by means of a feeding roller.
In the disc drive apparatus provided with the feeding roller, after discriminating a size of the disc shaped media which is guided to an inner portion of the apparatus by the feeding roller by means of a plurality of photo sensors, a solenoid is driven based on a discriminated signal from the photo sensors. In this type of disc drive apparatus, a position of a stopper pin is changed in correspondence to the size of the disc based on a series of operations.
However, in the disc drive apparatus having the structure mentioned above, since a lot of photo sensors are required for discriminating the size of the disc, there are problems that a high cost is required, and a complex control program is required. Further, there is a defect that a control system generates a malfunction if the photo sensors detect any foreign matter.
Accordingly, in another related art disk drive apparatus, the large and small disc shaped media are guided to a predetermined position by a link mechanism including a first switch actuating lever actuated by the small-diameter disc shaped media reaching a predetermined position, and a second switch actuating lever actuated by the large-diameter disc shaped media reaching a predetermined position, and a disc clamping motion and the like are executed by a switching operation by the first and second switch actuating levers (for example, Japanese Utility Model Application Publication No. H6-48603).
However, in the apparatus disclosed in the publication mentioned above, since a lot of parts are required for accurately position the large and small disc shaped media, in addition to the first and second switch actuating levers, there is a problem that the structure of the disc drive apparatus becomes complex. Further, since an end surface of the disc shaped media is brought into contact with the switch actuating lever, there is a requirement of a mechanism for moving the switch actuating lever apart from the disc end surface at a time of driving the disc shaped media.
The present invention is made by taking the circumstances mentioned above into consideration, and a main object of the present invention is to provide a disc drive apparatus which can position two kinds of large and small discs and read the discs well based on a simpler structure than the conventional one.